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Assessing the nonlinear association of environmental factors with antibiotic resistance genes (ARGs) in the Yangtze River Mouth, China. Sci Rep 2023; 13:20367. [PMID: 37989759 PMCID: PMC10663556 DOI: 10.1038/s41598-023-45973-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Accepted: 10/26/2023] [Indexed: 11/23/2023] Open
Abstract
The emergence of antibacterial resistance (ABR) is an urgent and complex public health challenge worldwide. Antibiotic resistant genes (ARGs) are considered as a new pollutant by the WHO because of their wide distribution and emerging prevalence. The role of environmental factors in developing ARGs in bacterial populations is still poorly understood. Therefore, the relationship between environmental factors and bacteria should be explored to combat ABR and propose more tailored solutions in a specific region. Here, we collected and analyzed surface water samples from Yangtze Delta, China during 2021, and assessed the nonlinear association of environmental factors with ARGs through a sigmoid model. A high abundance of ARGs was detected. Amoxicillin, phosphorus (P), chromium (Cr), manganese (Mn), calcium (Ca), and strontium (Sr) were found to be strongly associated with ARGs and identified as potential key contributors to ARG detection. Our findings suggest that the suppression of ARGs may be achieved by decreasing the concentration of phosphorus in surface water. Additionally, Group 2A light metals (e.g., magnesium and calcium) may be candidates for the development of eco-friendly reagents for controlling antibiotic resistance in the future.
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Challenges and opportunities of strain diversity in gut microbiome research. Front Microbiol 2023; 14:1117122. [PMID: 36876113 PMCID: PMC9981649 DOI: 10.3389/fmicb.2023.1117122] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 01/24/2023] [Indexed: 02/19/2023] Open
Abstract
Just because two things are related does not mean they are the same. In analyzing microbiome data, we are often limited to species-level analyses, and even with the ability to resolve strains, we lack comprehensive databases and understanding of the importance of strain-level variation outside of a limited number of model organisms. The bacterial genome is highly plastic with gene gain and loss occurring at rates comparable or higher than de novo mutations. As such, the conserved portion of the genome is often a fraction of the pangenome which gives rise to significant phenotypic variation, particularly in traits which are important in host microbe interactions. In this review, we discuss the mechanisms that give rise to strain variation and methods that can be used to study it. We identify that while strain diversity can act as a major barrier in interpreting and generalizing microbiome data, it can also be a powerful tool for mechanistic research. We then highlight recent examples demonstrating the importance of strain variation in colonization, virulence, and xenobiotic metabolism. Moving past taxonomy and the species concept will be crucial for future mechanistic research to understand microbiome structure and function.
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Metagenomic analysis of endemic viruses in oral secretions from Chinese pigs. Vet Med Sci 2022; 8:1982-1992. [PMID: 36047475 PMCID: PMC9514493 DOI: 10.1002/vms3.869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Background Pigs are unique reservoirs for virus ecology. Despite the increased use of improved biosecurity measures, pig viruses readily circulate in Chinese swine farms. Objectives The main objective of this study was to examine archived swine oral secretion samples with a panel of pan‐species viral assays such that we might better describe the viral ecology of swine endemic viruses in Chinese farms. Methodology Two hundred (n = 200) swine oral secretion samples, collected during 2015 and 2016 from healthy pigs on six swine farms in two provinces in China, were screened with molecular pan‐species assays for coronaviruses (CoVs), adenoviruses (AdVs), enteroviruses (EVs), and paramyxoviruses (PMV). Samples were also screened for porcine circovirus (PCV) 3, porcine reproductive and respiratory syndrome virus (PRRSV) and influenza A virus (IAV). Results Among 200 swine oral secretion samples, 152 (76.0%) were found to have at least one viral detection. Thirty‐four samples (17%) were positive for more than one virus, including 24 (70.5%) with dual detection and 10 (29.5%) with triple detection. Seventy‐eight (39.0%) samples were positive for porcine AdVs, 22 (11.0%) were positive for porcine CoVs, 21 (10.5%) were positive for IAVs, 13 (6.5%) were positive for PCV, 7 (3.5%) were positive for PMV, six (3.0%) were positive for PRRSV and five (2.5%) were positive for porcine EV. Conclusion Our findings underscore the high prevalence of numerous viruses among production pigs in China and highlight the need for routine, periodic surveillance for novel virus emergence with the goal of protecting pigs.
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Erratum: Azimuthal Anisotropy of K_{S}^{0} and Λ+Λ[over ¯] Production at Midrapidity from Au+Au Collisions at sqrt[s]_{NN}=130 GeV [Phys. Rev. Lett. 89, 132301 (2002)]. PHYSICAL REVIEW LETTERS 2021; 127:089901. [PMID: 34477449 DOI: 10.1103/physrevlett.127.089901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Indexed: 06/13/2023]
Abstract
This corrects the article DOI: 10.1103/PhysRevLett.89.132301.
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Erratum: Azimuthal Anisotropy at the Relativistic Heavy Ion Collider: The First and Fourth Harmonics [Phys. Rev. Lett. 92, 062301 (2004)]. PHYSICAL REVIEW LETTERS 2021; 127:069901. [PMID: 34420354 DOI: 10.1103/physrevlett.127.069901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Indexed: 06/13/2023]
Abstract
This corrects the article DOI: 10.1103/PhysRevLett.92.062301.
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Serum IP-10 and IL-7 levels are associated with disease severity of coronavirus disease 2019. Cytokine 2021; 142:155500. [PMID: 33810947 PMCID: PMC7973056 DOI: 10.1016/j.cyto.2021.155500] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 03/02/2021] [Accepted: 03/13/2021] [Indexed: 01/20/2023]
Abstract
We quantified the serum levels of 34 cytokines/chemokines in 30 patients with SARS-CoV-2 infection. Elevated levels of IP-10 and IL-7 were detected in the acute and convalescent stages of the infection and were highly associated with disease severity.
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Environmental and Aerosolized Severe Acute Respiratory Syndrome Coronavirus 2 Among Hospitalized Coronavirus Disease 2019 Patients. J Infect Dis 2020; 222:1798-1806. [PMID: 32905595 PMCID: PMC7499634 DOI: 10.1093/infdis/jiaa575] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 09/04/2020] [Indexed: 12/20/2022] Open
Abstract
During April and May 2020, we studied 20 patients hospitalized with coronavirus disease 2019 (COVID-19), their hospital rooms (fomites and aerosols), and their close contacts for molecular and culture evidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Among >400 samples, we found molecular evidence of virus in most sample types, especially the nasopharyngeal (NP), saliva, and fecal samples, but the prevalence of molecular positivity among fomites and aerosols was low. The agreement between NP swab and saliva positivity was high (89.5%; κ = 0.79). Two NP swabs collected from patients on days 1 and 7 post-symptom onset had evidence of infectious virus (2 passages over 14 days in Vero E6 cells). In summary, the low molecular prevalence and lack of viable SARS-CoV-2 virus in fomites and air samples implied low nosocomial risk of SARS-CoV-2 transmission through inanimate objects or aerosols.
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Detection of Severe Acute Respiratory Syndrome Coronavirus 2 RNA on Surfaces in Quarantine Rooms. Emerg Infect Dis 2020. [PMID: 32421495 DOI: 10.3201/2feid2609.201435] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/21/2023] Open
Abstract
We investigated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) environmental contamination in 2 rooms of a quarantine hotel after 2 presymptomatic persons who stayed there were laboratory-confirmed as having coronavirus disease. We detected SARS-CoV-2 RNA on 8 (36%) of 22 surfaces, as well as on the pillow cover, sheet, and duvet cover.
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Environmental bioaerosol surveillance as an early warning system for pathogen detection in North Carolina swine farms: A pilot study. Transbound Emerg Dis 2020; 68:361-367. [PMID: 32535997 DOI: 10.1111/tbed.13683] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 05/19/2020] [Accepted: 06/07/2020] [Indexed: 02/02/2023]
Abstract
Disease outbreaks can readily threaten swine production operations sometimes resulting in large economic losses. Pathogen surveillance in swine farms can be an effective approach for the early identification of new disease threats and the mitigation of transmission before broad dissemination among a herd occurs. Non-invasive environmental bioaerosol sampling could be an effective and affordable approach for conducting routine surveillance in farms, providing an additional tool for farmers to protect their animals and themselves from new disease threats. In this pilot study, we implemented a non-invasive, prospective bioaerosol sampling strategy in a swine farm located in the United States to detect economically important swine pathogens. Farm personnel collected air samples from two swine barns for 23 weeks between July and December 2017. Samples were then tested within 24 hr of collection by molecular techniques for a number of economically important swine pathogens. Of the 86 bioaerosol samples collected, 4 (4.7%) were positive for influenza A, 1 (1.2%) was positive for influenza D, 13 (15.1%) were positive for PCV2, and 13 (15.1%) were positive for PCV3. Overall, this pilot study showed that our bioaerosol surveillance strategy was feasible and able to generate data that could be quickly disseminated back to the farm stakeholders (within 24 hr). We were also able to identify PCV2, PCV3 and influenza A virus in air samples as clinical disease became apparent in the pigs, strongly suggesting that bioaerosol sampling can be used as an effective non-invasive surveillance approach for the detection of multiple pathogens in this and likely other animal production environments.
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Transmission Potential of Asymptomatic and Paucisymptomatic Severe Acute Respiratory Syndrome Coronavirus 2 Infections: A 3-Family Cluster Study in China. J Infect Dis 2020; 221:1948-1952. [PMID: 32319519 PMCID: PMC7188140 DOI: 10.1093/infdis/jiaa206] [Citation(s) in RCA: 61] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 04/21/2020] [Indexed: 01/22/2023] Open
Abstract
Data concerning the transmission of SARS-CoV-2 in asymptomatic and paucisymptomatic patients are lacking. We report a three-family cluster of infections involving asymptomatic and paucisymptomatic transmission. Eight (53%) of 15 members from three families were confirmed with SARS-CoV-2 infection. Of eight patients, three were asymptomatic and one was paucisymptomatic. An asymptomatic mother transmitted the virus to her son, and a paucisymptomatic father transmitted the virus to his three-month-old daughter. SARS-CoV-2 was detected in the environment of one household. The complete genomes of SARS-CoV-2 from the patients were >99.9% identical and were clustered with other SARS-CoV-2 sequences reported from China and other countries.
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Abstract
We investigated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) environmental contamination in 2 rooms of a quarantine hotel after 2 presymptomatic persons who stayed there were laboratory-confirmed as having coronavirus disease. We detected SARS-CoV-2 RNA on 8 (36%) of 22 surfaces, as well as on the pillow cover, sheet, and duvet cover.
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Evidence for Cross-species Influenza A Virus Transmission Within Swine Farms, China: A One Health, Prospective Cohort Study. Clin Infect Dis 2019; 66:533-540. [PMID: 29401271 DOI: 10.1093/cid/cix823] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 09/14/2017] [Indexed: 01/07/2023] Open
Abstract
Background Our understanding of influenza A virus transmission between humans and pigs is limited. Methods Beginning in 2015, we used a One Health approach and serial sampling to prospectively study 299 swine workers and 100 controls, their 9000 pigs, and 6 pig farm environments in China for influenza A viruses (IAVs) using molecular, culture, and immunological techniques. Study participants were closely monitored for influenza-like illness (ILI) events. Results Upon enrollment, swine workers had higher serum neutralizing antibody titers against swine H1N1 and higher nasal wash total immunoglobulin A (IgA) and specific IgA titers against swine H1N1 and H3N2 viruses. Over a period of 12 months, IAVs were detected by quantitative reverse-transcription polymerase chain reaction in 46 of 396 (11.6%) environmental swabs, 235 of 3300 (7.1%) pig oral secretion, 23 of 396 (5.8%) water, 20 of 396 (5.1%) aerosol, and 19 of 396 (4.8%) fecal-slurry specimens. Five of 32 (15.6%) participants with ILI events had nasopharyngeal swab specimens that were positive for IAV, and 17 (53.1%) demonstrated 4-fold rises in neutralization titers against a swine virus. Reassorted Eurasian avian-lineage H1N1, A(H1N1)pdm09-like, and swine-lineage H3N2 viruses were identified in pig farms. The A(H1N1)pdm09-like H1N1 viruses identified in swine were nearly genetically identical to the human H1N1 viruses isolated from the participants with ILI. Conclusions There was considerable evidence of A(H1N1)pdm09-like, swine-lineage H1N1, and swine-lineage H3N2 viruses circulating, likely reassorting, and likely crossing species within the pig farms. These data suggest that stronger surveillance for novel influenza virus emergence within swine farms is imperative.
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Genetic diversity of Anaplasma and Ehrlichia bacteria found in Dermacentor and Ixodes ticks in Mongolia. Ticks Tick Borne Dis 2019; 11:101316. [PMID: 31677968 DOI: 10.1016/j.ttbdis.2019.101316] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Revised: 10/15/2019] [Accepted: 10/16/2019] [Indexed: 10/25/2022]
Abstract
Anaplasma and Ehrlichia are tick-borne bacterial pathogens that cause human granulocytic anaplasmosis, human monocytic ehrlichiosis, and are severe threats to livestock economies like Mongolia. In this study, ticks were collected, identified, and pooled (n = 299) from three distinct environments across central Mongolia. Each pool was initially tested for Anaplasma/Ehrlichia using a 16S rRNA PCR assay that detects both genera, and specific PCR testing was done to identify those positive samples. Maximum likelihood estimation (MLE) of infection rates of ticks collected from the environment in Selenge aimag (province) found infection rates of Ixodes persulcatus ticks to be 2.0% (95% CI: 0.7, 4.3%) for A. phagocytophilum and 0.8% (95% CI: 0.1, 2.5%) for both nonspecific Ehrlichia and Anaplasma. Ehrlichia muris was only detected in I. persulcatus ticks collected from the Selenge aimag, where the MLE was 1.2% (95% CI: 0.1, 2.5%). The calculated MLE infection rate of Anaplasma spp. in questing Dermacentor nuttalli ticks ranged from 1.9% (95% CI: 1.1, 9.1%) in the Tov aimag to 2.3% (95% CI: 1.3, 10.8%) in the Selenge aimag. However, when examining MLE in ticks removed from livestock, estimates increase substantially, ranging from 7.8% (95% CI: 4.2, 13.3%) in Dornogovi to 22.5% (95% CI: 14.3, 34.3%) in Selenge, suggesting that livestock play a key role in disease maintenance. Considering the collective economic losses that can result from these pathogens and the potential for illness in nomadic herdsmen, these results highlight the need for enhanced TBD surveillance and prevention measures within Mongolia.
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Discrepancies between self-reported tick bites and evidence of tick-borne disease exposure among nomadic Mongolian herders. Zoonoses Public Health 2019; 66:480-486. [PMID: 30969028 PMCID: PMC6629472 DOI: 10.1111/zph.12579] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 02/18/2019] [Accepted: 03/11/2019] [Indexed: 12/28/2022]
Abstract
Twenty-six per cent of Mongolians live pastoral lifestyles, increasing their likelihood of exposure to ticks and placing them at a higher risk for contracting tick-borne diseases (TBDs). Anaplasma spp. and Rickettsia spp. have been identified in ticks, livestock and humans in Mongolia, but no known qualitative research has been conducted investigating the association between nomadic herder characteristics, tick bite history and exposure to TBDs. To better understand the association between self-reported tick bites and symptoms versus actual exposure to TBDs, this study paired serological data with 335 surveys administered to Mongolian herders, ages 12-69, from 2014 to 2015. Logistic regression results identified no significant associations between reported tick bites or symptoms with serological evidence of Anaplasma spp. and Rickettsia spp. controlling for age, gender and aimag. Among the 335 respondents who were seropositive to either Anaplasma spp. or Rickettsia spp., 32.9% self-reported experiencing abnormal symptoms such as redness, inflammation, headache, arthritis or fever after being bitten. Alternatively, 17.3% (58/335) of individuals reported experiencing symptoms following a tick bite in instances where serological results indicated no exposure to Anaplasma spp. or Rickettsia spp. Results also identified inconsistencies in reporting and seroprevalence among different age groups, with children having the highest reporting and treatment seeking rates but low levels of exposure in comparison with other groups. While survey results showed that individuals were aware of peak tick seasons and tick species that inhabit specific areas, 58% of heads of households (49/84) were unaware that ticks can cause disease in livestock or dogs. This study suggests that herders are an at-risk population in Mongolia with gaps in awareness of TBD risk. Increased surveillance paired with focused outreach to prevent TBDs targeted to the herder population is encouraged.
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The Drosophila Dbf4 ortholog Chiffon forms a complex with Gcn5 that is necessary for histone acetylation and viability. J Cell Sci 2019; 132:jcs.214072. [PMID: 30559249 DOI: 10.1242/jcs.214072] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 12/11/2018] [Indexed: 02/05/2023] Open
Abstract
Metazoans contain two homologs of the Gcn5-binding protein Ada2, Ada2a and Ada2b, which nucleate formation of the ATAC and SAGA complexes, respectively. In Drosophila melanogaster, there are two splice isoforms of Ada2b: Ada2b-PA and Ada2b-PB. Here, we show that only the Ada2b-PB isoform is in SAGA; in contrast, Ada2b-PA associates with Gcn5, Ada3, Sgf29 and Chiffon, forming the Chiffon histone acetyltransferase (CHAT) complex. Chiffon is the Drosophila ortholog of Dbf4, which binds and activates the cell cycle kinase Cdc7 to initiate DNA replication. In flies, Chiffon and Cdc7 are required in ovary follicle cells for gene amplification, a specialized form of DNA re-replication. Although chiffon was previously reported to be dispensable for viability, here, we find that Chiffon is required for both histone acetylation and viability in flies. Surprisingly, we show that chiffon is a dicistronic gene that encodes distinct Cdc7- and CHAT-binding polypeptides. Although the Cdc7-binding domain of Chiffon is not required for viability in flies, the CHAT-binding domain is essential for viability, but is not required for gene amplification, arguing against a role in DNA replication.
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Evidence for transovarial transmission of tick-borne rickettsiae circulating in Northern Mongolia. PLoS Negl Trop Dis 2018; 12:e0006696. [PMID: 30148847 PMCID: PMC6128658 DOI: 10.1371/journal.pntd.0006696] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 09/07/2018] [Accepted: 07/17/2018] [Indexed: 12/02/2022] Open
Abstract
Transstadial transmission of tick-borne rickettsiae has been well documented. Few studies, however, have evaluated the role of transovarial transmission of tick-borne rickettsiae, particularly in nature within the host-vector ecosystem. This cross-sectional study aimed to understand the role of transovarial transmission of tick-borne rickettsiae among feeding ticks at different life stages. Tick eggs laid by engorged wild-caught adult female ticks were pooled and tested for Rickettsia spp. and Anaplasma/Ehrlichia spp. using molecular techniques, while adult fed ticks were tested individually. Additionally, larval and nymphal ticks were collected in the wild from small mammals, pooled and tested for Rickettsia spp. and Anaplasma/Ehrlichia spp. There were 38 fed adult and 618 larvae/nymphs (60 pools total) Dermacentor spp. ticks collected from livestock and rodents. All individual adult ticks and tick pools were positive for Rickettsia spp. While none of the larvae/nymphs were positive for Anaplasma/Ehrlichia spp., two adult fed ticks were positive. Rickettsia spp. DNA was detected in 91% (30/33) of the pooled eggs tested, and one pool of eggs tested positive for Anaplasma/Ehrlichia spp. Sequencing data revealed Rickettsia spp. shared ≥99% identity with R. raoultii ompA. Anaplasma/Ehrlichia spp. shared ≥89% identity with A. ovis 16S ribosomal RNA. This study identified potential transovarial transmission of Rickettsia spp. and Anaplasma spp. among D. nuttalli ticks. Additional studies are needed to further assess the proportion of transovarial transmission occurring in nature to better understand the burden and disease ecology of tick-borne rickettsiae in Mongolia. In this study, we evaluate the probability or likelihood that tick-borne rickettsiae might be transmitted vertically from wild engorged adult female ticks collected throughout the Northern region of Mongolia during the summer of 2016. While significant effort has been directed to study tick-borne rickettsiae, this public health challenge is complicated by the limited knowledge and understanding of tick and tick-borne rickettsiae ecology within Mongolia. Tick-borne rickettsiae of concern to humans and animals in this region of the world are Rickettsia spp., Anaplasma spp., and Ehrlichia spp. Using molecular techniques, we detected rickettsiae among all Dermacentor spp. tick life stages and demonstrated potential vertical transmission of Rickettsia spp., and Anaplasma spp. among wild engorged adult female Dermacentor nuttalli ticks. We believe our findings provide important information regarding the ecology of key rickettsiae associated with tick-borne disease in Mongolia.
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Adenovirus Type 21 Outbreak Among Lung Transplant Patients at a Large Tertiary Care Hospital. Open Forum Infect Dis 2018; 5:ofy188. [PMID: 30151413 PMCID: PMC6105090 DOI: 10.1093/ofid/ofy188] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Accepted: 07/27/2018] [Indexed: 12/20/2022] Open
Abstract
Here we summarize an April 2016, 7-patient cluster of human adenovirus (HAdV) infections in a cardiothoracic surgery intensive care unit. We show that the patients were infected with a single HAdV21b type. Rapid HAdV typing diagnostics and effective antiviral interventions are needed for immunocompromised patients suffering from HAdV infections.
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Surveillance for respiratory and diarrheal pathogens at the human-pig interface in Sarawak, Malaysia. PLoS One 2018; 13:e0201295. [PMID: 30052648 PMCID: PMC6063427 DOI: 10.1371/journal.pone.0201295] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 07/12/2018] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND The large livestock operations and dense human population of Southeast Asia are considered a hot-spot for emerging viruses. OBJECTIVES To determine if the pathogens adenovirus (ADV), coronavirus (CoV), encephalomyocarditis virus (EMCV), enterovirus (EV), influenza A-D (IAV, IBV, ICV, and IDV), porcine circovirus 2 (PCV2), and porcine rotaviruses A and C (RVA and RVC), are aerosolized at the animal-interface, and if humans working in these environments are carrying these viruses in their nasal airways. STUDY This cross-sectional study took place in Sarawak, Malaysia among 11 pig farms, 2 abattoirs, and 3 animal markets in June and July of 2017. Pig feces, pig oral secretions, bioaerosols, and worker nasal wash samples were collected and analyzed via rPCR and rRT-PCR for respiratory and diarrheal viruses. RESULTS In all, 55 pig fecal, 49 pig oral or water, 45 bioaerosol, and 78 worker nasal wash samples were collected across 16 sites. PCV2 was detected in 21 pig fecal, 43 pig oral or water, 3 bioaerosol, and 4 worker nasal wash samples. In addition, one or more bioaerosol or pig samples were positive for EV, IAV, and RVC, and one or more worker samples were positive for ADV, CoV, IBV, and IDV. CONCLUSIONS This study demonstrates that nucleic acids from a number of targeted viruses were present in pig oral secretions and pig fecal samples, and that several viruses were detected in bioaerosol samples or in the nasal passages of humans with occupational exposure to pigs. These results demonstrate the need for future research in strengthening viral surveillance at the human-animal interface, specifically through expanded bioaerosol sampling efforts and a seroepidemiological study of individuals with exposure to pigs in this region for PCV2 infection.
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A cross-sectional study of small mammals for tick-borne pathogen infection in northern Mongolia. Infect Ecol Epidemiol 2018; 8:1450591. [PMID: 29696073 PMCID: PMC5912330 DOI: 10.1080/20008686.2018.1450591] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 02/28/2018] [Indexed: 11/02/2022] Open
Abstract
Background: Tick-borne pathogens (TBPs) are frequently studied in developed nations but are often neglected in emerging countries. In Mongolia, TBP research is especially sparse, with few research reports focusing upon human and domestic animal disease and tick ecology. However, little information exists on TBPs in small mammals. Methods: In this 2016 cross-sectional pilot study, we sought to uniquely study wildlife for TBPs. We live-trapped small mammals, and tested their whole blood, serum and ear biopsy samples for molecular or serological evidence of Borrelia spp., Rickettsia spp., and Anaplasma spp./Ehrlichia spp. Results: Of 64 small mammals collected, 56.0%, 39.0% and 0.0% of animals were positive by molecular assays for Borrelia spp., Rickettsia spp., and Anaplasma spp./Erhlicia spp., respectively. 41.9% were seropositive for A. phagocytophilum and 24.2% of animals were seropositive for Rickettsia rickettsii. Conclusion: This pilot data demonstrates evidence of a number of TBPs among small mammal populations in northern Mongolia and suggests the need to further investigate what role these mammals play in human and domestic animal disease.
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Estimated seroprevalence of Anaplasma spp. and spotted fever group Rickettsia exposure among herders and livestock in Mongolia. Acta Trop 2018; 177:179-185. [PMID: 29054570 PMCID: PMC5671362 DOI: 10.1016/j.actatropica.2017.10.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 10/02/2017] [Accepted: 10/16/2017] [Indexed: 10/18/2022]
Abstract
BACKGROUND To better understand the epidemiology of tick-borne disease in Mongolia, a comprehensive seroprevalence study was conducted investigating exposure to Anaplasma spp. and spotted fever group (SFG) Rickettsia spp. in nomadic herders and their livestock across three provinces from 2014 to 2015. METHODS Blood was collected from 397 herders and 2370 livestock, including sheep, goats, cattle, horses and camels. Antibodies against Anaplasma spp. and SFG Rickettsia were determined by indirect immunofluorescence using commercially available slides coated with Anaplasma phagocytophilum and Rickettsia rickettsii antigens. Logistic regression was used to determine if the odds of previous exposure differed by gender, location, and species, with or without adjustment for age. To examine the association between seroprevalence and environmental variables we used ArcGIS to circumscribe the five major clusters where human and animal data were collected. RESULTS Anaplasma spp. exposure was detected in 37.3% (136/365) of humans and 47.3% (1120/2370) of livestock; SFG Rickettsia exposure was detected in 19.5% (73/374) humans and 20.4% (478/2342) livestock. Compared to the southern province (aimag) of Dornogovi, located in the Gobi Desert, humans were significantly more likely to be exposed to Anaplasma spp. and SFG Rickettsia in the northern provinces of Tov (OR=7.3, 95% CI: 3.5, 15.1; OR=3.3, 95% CI: 1.7, 7.5), and Selenge (OR=6.9, 95% CI: 3.4, 14.0; OR=2.2, 95% CI: 1.1, 4.8). CONCLUSION The high seroprevalence of Anaplasma spp. and SFG Rickettsia in humans and livestock suggests that exposure to tick-borne pathogens may be common in herders and livestock in Mongolia, particularly in the more northern regions of the country. Until more is known about these pathogens in Mongolia, physicians and veterinarians in the countryside should consider testing for Anaplasma and SFG Rickettsia infections and treating clinically compatible cases, while public health authorities should expand surveillance efforts for these emerging infections.
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Prevalence of Respiratory Polyomaviruses Among Pediatric Patients With Respiratory Symptoms in Singapore. Front Pediatr 2018; 6:228. [PMID: 30175090 PMCID: PMC6107759 DOI: 10.3389/fped.2018.00228] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/09/2018] [Accepted: 07/26/2018] [Indexed: 11/30/2022] Open
Abstract
Background: Although WU polyomavirus (WU) and KI polyomavirus (KI) have been demonstrated to infect the human respiratory tract, it remains unclear if WU or KI cause human disease. We sought to further investigate the relationship between WU and KI infection and respiratory disease in a pediatric population with respiratory symptoms in Singapore. Methods: We conducted a cross-sectional study of pediatric patients with respiratory symptoms in a Singaporean pediatrics hospital. Upon consent, residual respiratory samples from pediatric inpatients, previously screened for common respiratory viruses, were collected and further screened for WU and KI using qPCR. The amplicons of positive samples were sequenced for confirmation. The severity of a patient's illness was assessed by chart review post-discharge looking for clinical markers of respiratory status such as presenting symptoms, diagnoses, and interventions. Results: From December 2016 to April 2017, 201 patients with residual respiratory samples were enrolled in the study. The average age of all participants recruited was 45 months. WU and KI were detected in 13% (26/201) and 3% (6/201) of patients, respectively. Conducting bivariate and multivariate modeling, patients with WU or KI positivity were not at increased risk of SARI, need for additional oxygen, intravenous fluids, and did not receive additional oral antibiotics or bronchodilators during admission. In contrast, patients with RSV detections were at increased risk of requiring supplemental oxygen during hospital admission. Conclusion: While limited in sample size, our pilot study data do not support the hypothesis that molecular evidence of WU or KI was associated with increased morbidity among a sample of general, pediatric patients with respiratory illness in Singapore.
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Epidemiological study of people living in rural North Carolina for novel respiratory viruses. Zoonoses Public Health 2017; 65:e265-e269. [PMID: 29265702 PMCID: PMC7165517 DOI: 10.1111/zph.12436] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Indexed: 12/14/2022]
Abstract
During the last 10 years, scientists have grown increasingly aware that emerging respiratory viruses are often zoonotic in their origin. These infections can originate from or be amplified in livestock. Less commonly recognized are instances when humans have transmitted their respiratory pathogens to animals (reverse zoonoses). Even with this knowledge of viral exchange at the human–livestock interface, few studies have been conducted to understand this cross‐over. In this pilot study, we examined persons with influenza‐like illness at an outpatient clinic for evidence of infection with novel zoonotic respiratory pathogens in rural North Carolina where there are dense swine and poultry farming. Environmental air sampling was also conducted. From July 2016 to March 2017, a total of 14 human subjects were enrolled and sampled, and 192 bioaerosol samples were collected. Of the 14 human subject samples molecularly tested, three (21.4%) were positive for influenza A, one (7.1%) for influenza B and one (7.1%) for human enterovirus. Of the 192 bioaerosol samples collected and tested by real‐time RT‐PCR or PCR, three (1.6%) were positive for influenza A and two (1.0%) for adenovirus. No evidence was found for novel zoonotic respiratory viruses.
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Publisher's Note: JLab Measurements of the ^{3}He Form Factors at Large Momentum Transfers [Phys. Rev. Lett. 119, 162501 (2017)]. PHYSICAL REVIEW LETTERS 2017; 119:209901. [PMID: 29219338 DOI: 10.1103/physrevlett.119.209901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Indexed: 06/07/2023]
Abstract
This corrects the article DOI: 10.1103/PhysRevLett.119.162501.
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JLab Measurements of the ^{3}He Form Factors at Large Momentum Transfers. PHYSICAL REVIEW LETTERS 2017; 119:162501. [PMID: 29099223 DOI: 10.1103/physrevlett.119.162501] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2016] [Indexed: 06/07/2023]
Abstract
The charge and magnetic form factors, F_{C} and F_{M}, respectively, of ^{3}He are extracted in the kinematic range 25 fm^{-2}≤Q^{2}≤61 fm^{-2} from elastic electron scattering by detecting ^{3}He recoil nuclei and scattered electrons in coincidence with the two High Resolution Spectrometers of the Hall A Facility at Jefferson Lab. The measurements find evidence for the existence of a second diffraction minimum for the magnetic form factor at Q^{2}=49.3 fm^{-2} and for the charge form factor at Q^{2}=62.0 fm^{-2}. Both minima are predicted to exist in the Q^{2} range accessible by this Jefferson Lab experiment. The data are in qualitative agreement with theoretical calculations based on realistic interactions and accurate methods to solve the three-body nuclear problem.
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Abstract
There have been many terms used to describe the One Health concept, including movement, strategy, framework, agenda, approach, among others. However, the inter-relationships of the disciplines engaged in the One Health concept have not been well described. To identify and better elucidate the internal feedback mechanisms of One Health, we employed a system dynamics approach. First, a systematic literature review was conducted via searches in PubMed, Web of Knowledge, and ProQuest with the search terms: 'One Health' and (concept* or approach*). In addition, we used the HistCite® tool to add significant articles on One Health to the library. Then, of the 2368 articles identified, 19 were selected for evaluating the inter-relationships of disciplines engaged in One Health. Herein, we report a visually rich, theoretical model regarding interactions of various disciplines and complex problem descriptors engaged in One Health problem solving. This report provides a conceptual framework for future descriptions of the interdisciplinary engagements involved in One Health.
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The Use of Bioaerosol Sampling for Airborne Virus Surveillance in Swine Production Facilities: A Mini Review. Front Vet Sci 2017; 4:121. [PMID: 28798919 PMCID: PMC5529434 DOI: 10.3389/fvets.2017.00121] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 07/10/2017] [Indexed: 12/30/2022] Open
Abstract
Modern swine production facilities typically house dense populations of pigs and may harbor a variety of potentially zoonotic viruses that can pass from one pig generation to another and periodically infect human caretakers. Bioaerosol sampling is a common technique that has been used to conduct microbial risk assessments in swine production, and other similar settings, for a number of years. However, much of this work seems to have been focused on the detection of non-viral microbial agents (i.e., bacteria, fungi, endotoxins, etc.), and efforts to detect viral aerosols in pig farms seem sparse. Data generated by such studies would be particularly useful for assessments of virus transmission and ecology. Here, we summarize the results of a literature review conducted to identify published articles related to bioaerosol generation and detection within swine production facilities, with a focus on airborne viruses. We identified 73 scientific reports, published between 1991 and 2017, which were included in this review. Of these, 19 (26.7%) used sampling methodology for the detection of viruses. Our findings show that bioaerosol sampling methodologies in swine production settings have predominately focused on the detection of bacteria and fungi, with no apparent standardization between different approaches. Information, specifically regarding virus aerosol burden in swine production settings, appears to be limited. However, the number of viral aerosol studies has markedly increased in the past 5 years. With the advent of new sampling technologies and improved diagnostics, viral bioaerosol sampling could be a promising way to conduct non-invasive viral surveillance among swine farms.
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A Case of Influenza A (H3N2) Complicated by Community-Acquired Pneumonia and Death in a Young Healthy Adult during the 2013-2014 Season. Front Public Health 2017; 5:1. [PMID: 28229066 PMCID: PMC5296325 DOI: 10.3389/fpubh.2017.00001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 01/13/2017] [Indexed: 01/02/2023] Open
Abstract
With multiple available vaccines and antivirals, seasonal influenza A is typically a self-limited acutely debilitating illness in young healthy adults. Here, we illustrate unexpected morbidity and mortality in a relatively young and healthy patient seen at a large tertiary care academic medical center for seasonal influenza A (H3N2) complicated by community-acquired pneumonia, hypoxic respiratory failure, septic shock, and death.
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Serological evidence of ongoing transmission of dengue virus in permanent residents of Key West, Florida. Vector Borne Zoonotic Dis 2017; 14:783-7. [PMID: 25409268 DOI: 10.1089/vbz.2014.1665] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022] Open
Abstract
INTRODUCTION Dengue fever is the most important mosquito-borne viral disease in the world, with 40% of the global population at risk of infection. Dengue virus is responsible for infections in over 100 countries, including the Americas and Caribbean Basin; however, it has been largely eradicated from the United States through the implementation of effective vector control programs. However, between 2009 and 2010, 27 permanent residents of Key West, Florida, were reported to have locally acquired infections, marking the first autochthonous cases detected in Florida since 1934. Despite this recent and unusual transmission, and the potential risk of serious illness associated with sequential infections, no active surveillance had been conducted since. MATERIALS AND METHODS A serosurvey of permanent residents of Key West, Florida, was conducted in March of 2012. After informed consent, enrolled participants (n=173) were given a dengue virus rapid diagnostic test and completed a corresponding questionnaire. RESULTS The presence of immunoglobulin G (IgG) antibodies was indicated in 12 participants (6.9%), all of whom reported travel to endemic countries within the past 2 years. Surprisingly, six participants (3.5%) without any recent travel outside the state of Florida gave positive results for IgM antibodies. The presence of birdbaths and bromeliads on the property and sleeping outdoors emerged as significant factors related to previous exposure, whereas home air conditioning without the use of open windows and the use of mosquito repellent were protective. CONCLUSIONS These findings suggest local transmission occurred in Key West in early 2012, indicating that transmission may not have subsided in 2010.
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Aerosolized avian influenza A (H5N6) virus isolated from a live poultry market, China. J Infect 2017; 74:89-91. [DOI: 10.1016/j.jinf.2016.08.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 08/03/2016] [Indexed: 12/14/2022]
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Bioaerosol Sampling in Clinical Settings: A Promising, Noninvasive Approach for Detecting Respiratory Viruses. Open Forum Infect Dis 2016; 4:ofw259. [PMID: 28480252 PMCID: PMC5413998 DOI: 10.1093/ofid/ofw259] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 11/29/2016] [Accepted: 12/02/2016] [Indexed: 12/15/2022] Open
Abstract
Background Seeking a noninvasive method to conduct surveillance for respiratory pathogens, we sought to examine the usefulness of 2 types of off-the-shelf aerosol samplers to detect respiratory viruses in Singapore. Methods In this pilot study, we ran the aerosol samplers several times each week with patients present in the patient waiting areas at 3 primary health clinics during the months of April and May 2016. We used a SKC BioSampler with a BioLite Air Sampling Pump (run for 60 min at 8 L/min) and SKC AirChek TOUCH personal air samplers with polytetrafluoroethylene Teflon filter cassettes (run for 180 min at 5 L/min). The aerosol specimens and controls were studied with molecular assays for influenza A virus, influenza B virus, adenoviruses, and coronaviruses. Results Overall, 16 (33.3%) of the 48 specimens indicated evidence of at least 1 respiratory pathogen, with 1 (2%) positive for influenza A virus, 3 (6%) positive for influenza B virus, and 12 (25%) positive for adenovirus. Conclusions Although we were not able to correlate molecular detection with individual patient illness, patients with common acute respiratory illnesses were present during the samplings. Combined with molecular assays, it would suggest that aerosol sampling has potential as a noninvasive method for novel respiratory virus detection in clinical settings.
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Abstract
Usutu (USUV) and Zika (ZIKV) viruses are emerging arboviruses of significant medical and veterinary importance. These viruses have not been studied as well as other medically important arboviruses such as West Nile (WNV), dengue (DENV), or chikungunya (CHIKV) viruses. As such, information regarding the behavior of ZIKV and USUV viruses in the laboratory is dated. Usutu virus re-emerged in Austria in 2001 and has since spread throughout the European and Asian continents causing significant mortality among birds. Zika virus has recently appeared in the Western Hemisphere and has exhibited high rates of birth defects and sexual transmission. Information about the characteristics of USUV and ZIKV viruses are needed to better understand the transmission, dispersal, and adaptation of these viruses in new environments. Since their initial characterization in the middle of last century, technologies and reagents have been developed that could enhance our abilities to study these pathogens. Currently, standard laboratory methods for these viruses are limited to 2–3 cell lines and many assays take several days to generate meaningful data. The goal of this study was to characterize these viruses in cells from multiple diverse species. Cell lines from 17 species were permissive to both ZIKV and USUV. These viruses were able to replicate to significant titers in most of the cell lines tested. Moreover, cytopathic effects were observed in 8 of the cell lines tested. These data indicate that a variety of cell lines can be used to study ZIKV and USUV infection and may provide an updated foundation for the study of host-pathogen interactions, model development, and the development of therapeutics. Usutu and Zika viruses are arboviruses of significant medical and veterinary outbreaks in recent years. Currently, standard laboratory methods for these viruses are limited to 2–3 cell lines. Here, our studies demonstrate that Zika and Usutu viruses are able to replicate in cells from a wide range of animal cell lines. The data will allow for further study of the potential for evolution of these viruses in other hosts.
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Bioaerosol Sampling in Modern Agriculture: A Novel Approach for Emerging Pathogen Surveillance? J Infect Dis 2016; 214:537-45. [PMID: 27190187 DOI: 10.1093/infdis/jiw180] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 04/27/2016] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Modern agricultural practices create environmental conditions conducive to the emergence of novel pathogens. Current surveillance efforts to assess the burden of emerging pathogens in animal production facilities in China are sparse. In Guangdong Province pig farms, we compared bioaerosol surveillance for influenza A virus to surveillance in oral pig secretions and environmental swab specimens. METHODS During the 2014 summer and fall/winter seasons, we used 3 sampling techniques to study 5 swine farms weekly for influenza A virus. Samples were molecularly tested for influenza A virus, and positive specimens were further characterized with culture. Risk factors for influenza A virus positivity for each sample type were assessed. RESULTS Seventy-one of 354 samples (20.1%) were positive for influenza A virus RNA by real-time reverse-transcription polymerase chain reaction analysis. Influenza A virus positivity in bioaerosol samples was a statistically significant predictor for influenza A virus positivity in pig oral secretion and environmental swab samples. Temperature of <20°C was a significant predictor of influenza A virus positivity in bioaerosol samples. DISCUSSIONS Climatic factors and routine animal husbandry practices may increase the risk of human exposure to aerosolized influenza A viruses in swine farms. Data suggest that bioaerosol sampling in pig barns may be a noninvasive and efficient means to conduct surveillance for novel influenza viruses.
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Seroepidemiological Study of Interepidemic Rift Valley Fever Virus Infection Among Persons with Intense Ruminant Exposure in Madagascar and Kenya. Am J Trop Med Hyg 2015; 93:1364-1370. [PMID: 26458775 PMCID: PMC4674260 DOI: 10.4269/ajtmh.15-0383] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2015] [Accepted: 08/16/2015] [Indexed: 12/26/2022] Open
Abstract
In this cross-sectional seroepidemiological study we sought to examine the evidence for circulation of Rift Valley fever virus (RVFV) among herders in Madagascar and Kenya. From July 2010 to June 2012, we enrolled 459 herders and 98 controls (without ruminant exposures) and studied their sera (immunoglobulin G [IgG] and IgM through enzyme-linked immunosorbent assay [ELISA] and plaque reduction neutralization test [PRNT] assays) for evidence of previous RVFV infection. Overall, 59 (12.9%) of 459 herders and 7 (7.1%) of the 98 controls were positive by the IgG ELISA assay. Of the 59 ELISA-positive herders, 23 (38.9%) were confirmed by the PRNT assay (21 from eastern Kenya). Two of the 21 PRNT-positive study subjects also had elevated IgM antibodies against RVFV suggesting recent infection. Multivariate modeling in this study revealed that being seminomadic (odds ratio [OR] = 6.4, 95% confidence interval [CI] = 2.1-15.4) was most strongly associated with antibodies against RVFV. Although we cannot know when these infections occurred, it seems likely that some interepidemic RVFV infections are occurring among herders. As there are disincentives regarding reporting RVFV outbreaks in livestock or wildlife, it may be prudent to conduct periodic, limited, active seroepidemiological surveillance for RVFV infections in herders, especially in eastern Kenya.
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Abstract
Because little is known about the ecology of influenza viruses in camels, 460 nasal swab specimens were collected from healthy (no overt illness) Bactrian camels in Mongolia during 2012. One specimen was positive for influenza A virus (A/camel/Mongolia/335/2012[H3N8]), which is phylogenetically related to equine influenza A(H3N8) viruses and probably represents natural horse-to-camel transmission.
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Serological Evidence and Risk Factors for Swine Influenza Infections among Chinese Swine Workers in Guangdong Province. PLoS One 2015; 10:e0128479. [PMID: 26016740 PMCID: PMC4446356 DOI: 10.1371/journal.pone.0128479] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Accepted: 04/27/2015] [Indexed: 01/15/2023] Open
Abstract
During July to September 2014, we performed a controlled, cross-sectional, seroepidemiologic study among 203 swine workers and 115 control subjects in Guangdong Province. Sera were tested using a hemagglutination inhibition assay against locally-isolated swine H3N2 and H1N1 viruses and commercially-obtained human influenza viral antigens. We found swine workers had a greater prevalence and odds of seropositivity against the swine H3N2 virus (17.3% vs. 7.0%; adjusted OR, 3.4; 95% CI, 1.1 -10.7). Younger age, self-report of a respiratory illness during the last 12 months, and seropositivity against seasonal H3N2 virus were identified as significant risk factors for seropositivity against swine H3N2 virus. As swine workers in China may be exposed to novel influenza viruses, it seems prudent for China to conduct special surveillance for such viruses among them. It also seems wise to offer such workers seasonal influenza vaccines with a goal to reduce cross-species influenza virus transmission.
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Evaluation of inapparent dengue infections during an outbreak in Southern China. PLoS Negl Trop Dis 2015; 9:e0003677. [PMID: 25826297 PMCID: PMC4380470 DOI: 10.1371/journal.pntd.0003677] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 03/05/2015] [Indexed: 11/18/2022] Open
Abstract
Few studies evaluating inapparent dengue virus (DENV) infections have been conducted in China. In 2013, a large outbreak of DENV occurred in the city of Zhongshan, located in Southern China, which provided an opportunity to assess the clinical spectrum of disease. During the outbreak, an investigation of 887 index case contacts was conducted to evaluate inapparent and symptomatic DENV infections. Post-outbreak, an additional 815 subjects from 4 towns with, and 350 subjects from 2 towns without reported autochthonous DENV transmission, as determined by clinical diagnosis, were evaluated for serological evidence of dengue IgG antibodies. Between July and November 2013, there were 19 imported and 809 autochthonous dengue cases reported in Zhongshan. Of 887 case contacts enrolled during the outbreak, 13 (1.5%) exhibited symptomatic DENV infection, while 28 (3.2%) were inapparent. The overall I:S ratio was 2.2:1 (95% CI: 1.1-4.2:1). Post-outbreak serological data showed that the proportion of DENV IgG antibody detection from the 4 towns with and the 2 towns without reported DENV transmission was 2.7% (95% CI: 1.6%-3.8%) and 0.6% (95% CI: 0-1.4%), respectively. The I:S ratio in the 3 towns where clinical dengue cases were predominately typed as DENV-1 was 11.0:1 (95% CI: 3.7-∞:1). The ratio in the town where DENV-3 was predominately typed was 1.0:1 (95% CI: 0.5-∞:1). In this cross-sectional study, data suggests a high I:S ratio during a documented outbreak in Zhongshan, Southern China. These results have important implications for dengue control, implying that inapparent cases might influence DENV transmission more than previously thought. In this report, we evaluated individuals with symptomatic and asymptomatic dengue virus (DENV) infections during a 2013 DENV outbreak in Southern China, as well as performed post-outbreak serological testing for DENV IgG antibodies, to better understand DENV transmission. These findings suggest a high rate of asymptomatic cases, which has important implications for future dengue control.
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A Systematic Review and Meta-Analysis of the Seroprevalence of Influenza A(H9N2) Infection Among Humans. J Infect Dis 2015; 212:562-9. [PMID: 25712969 DOI: 10.1093/infdis/jiv109] [Citation(s) in RCA: 66] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 02/17/2015] [Indexed: 01/31/2023] Open
Abstract
INTRODUCTION Given that influenza A(H9N2) is recognized as a pandemic threat, we evaluated the overall burden of influenza A(H9N2) infections among avian-exposed human populations. METHODS We performed a systematic search of PubMed, AGRICOLA, and CAB Abstracts databases for literature published during 1997-2013. Studies reporting serological evidence of human influenza A(H9N2) infection among avian-exposed populations were included. We used a World Health Organization (WHO)-recommended case definition for serological evidence of infection based on results of hemagglutination inhibition (HI) and microneutralization (MN) assays. We calculated overall seroprevalence through a random effects meta-analysis model. RESULTS Seroprevalence data reported by the studies ranged from 1% to 43% (median, 9%) by HI, which was not significantly different from the seroprevalence estimated through the WHO-recommended case definition (median, 1.3%; range, 0.5%-42.6%). Reported seroprevalence by MN ranged from 0.6% to 9% (median, 2.7%), which was greater than the seroprevalence estimated through the WHO-recommended case definition (median, 0.3%; range, 0.1%-1.4%). CONCLUSIONS A small proportion of avian-exposed humans had evidence of influenza A(H9N2) infection. As the virus has a near global distribution in poultry, it seems likely that present surveillance efforts are missing mild or asymptomatic infections among avian-exposed persons. It seems prudent to closely monitor avian-exposed populations for influenza A(H9N2) infection to provide prepandemic warnings.
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Elevated antibodies against Rift Valley fever virus among humans with exposure to ruminants in Saudi Arabia. Am J Trop Med Hyg 2015; 92:739-43. [PMID: 25646253 DOI: 10.4269/ajtmh.14-0575] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 11/14/2014] [Indexed: 11/07/2022] Open
Abstract
In 2000, an outbreak of Rift Valley fever virus (RVFV) occurred in the Kingdom of Saudi Arabia (KSA). Since then there have been sparse efforts to monitor for RVFV reemergence. During 2012, we enrolled 300 individuals with ruminant exposure and 50 age-group matched non-exposed controls in southwestern KSA, in a cross-sectional epidemiological study of RVFV. Sera from the participants were screened with an enzyme-linked immunosorbent assay (ELISA) for anti-RVFV IgG antibodies of which 39 (11.1%) were positive. Sixteen (41.0%) of those 39 were also positive by a plaque reduction neutralization assay (PRNT). The PRNT-positive subjects were further studied with an IgM ELISA and one was positive. No RVFV was detected in the 350 sera using real-time reverse transcription polymerase chain reaction. Contact with cattle (odds ratio [OR] = 3.16, 95% confidence interval [CI] 1.01, 9.90) and a history of chronic medical illness (OR = 6.41, 95% CI 1.75, 23.44) were associated with greater odds of RVFV seropositivity by PRNT. The IgM-positive participant was 36 years of age, and reported multiple risk factors for ruminant contact. Although these findings simply may be vestiges of the 2000 epidemic, KSA's frequent visits from pilgrims and importations of live animals from RVFV-endemic areas suggest that more comprehensive surveillance for imported RVFV virus in ruminants, mosquitoes, and travelers is imperative.
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Sparse evidence of MERS-CoV infection among animal workers living in Southern Saudi Arabia during 2012. Influenza Other Respir Viruses 2014; 9:64-7. [PMID: 25470665 PMCID: PMC4353318 DOI: 10.1111/irv.12287] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/03/2014] [Indexed: 01/24/2023] Open
Abstract
Middle East respiratory syndrome coronavirus (MERS-CoV) is an emerging viral pathogen that primarily causes respiratory illness. We conducted a seroprevalence study of banked human serum samples collected in 2012 from Southern Saudi Arabia. Sera from 300 animal workers (17% with daily camel exposure) and 50 non-animal-exposed controls were examined for serological evidence of MERS-CoV infection by a pseudoparticle MERS-CoV spike protein neutralization assay. None of the sera reproducibly neutralized the MERS-CoV-pseudotyped lentiviral vector. These data suggest that serological evidence of zoonotic transmission of MERS-CoV was not common among animal workers in Southern Saudi Arabia during July 2012.
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[Emerging adenovirus threats: should China develop a vaccine-oriented prevention strategy?]. ZHONGHUA YU FANG YI XUE ZA ZHI [CHINESE JOURNAL OF PREVENTIVE MEDICINE] 2014; 48:1030-1034. [PMID: 25619210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
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Abstract
PURPOSE Elderly oncology patients are not enrolled in early-phase trials in proportion to the numbers of geriatric patients with cancer. There may be concern that elderly patients will not tolerate investigational agents as well as younger patients, resulting in a disproportionate number of dose-limiting toxicities (DLT). Recent single-institution studies provide conflicting data on the relationship between age and DLT. EXPERIMENTAL DESIGN We retrospectively reviewed data about patients treated on single-agent, dose-escalation, phase I clinical trials sponsored by the Cancer Therapy Evaluation Program (CTEP) of the National Cancer Institute. Patients' dose levels were described as a percentage of maximum tolerated dose, the highest dose level at which <33% of patients had a DLT, or recommended phase II dose (RP2D). Mixed-effect logistic regression models were used to analyze relationships between the probability of a DLT and age and other explanatory variables. RESULTS Increasing dose, increasing age, and worsening performance status (PS) were significantly related to an increased probability of a DLT in this model (P < 0.05). There was no association between dose level administered and age (P = 0.57). CONCLUSIONS This analysis of phase I dose-escalation trials, involving more than 500 patients older than 70 years of age, is the largest reported. As age and dose level increased and PS worsened, the probability of a DLT increased. Although increasing age was associated with occurrence of DLT, this risk remained within accepted thresholds of risk for phase I trials. There was no evidence of age bias on enrollment of patients on low or high dose levels.
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JLab measurement of the 4He charge form factor at large momentum transfers. PHYSICAL REVIEW LETTERS 2014; 112:132503. [PMID: 24745410 DOI: 10.1103/physrevlett.112.132503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Indexed: 06/03/2023]
Abstract
The charge form factor of 4He has been extracted in the range 29 fm(-2) ≤ Q2 ≤ 77 fm(-2) from elastic electron scattering, detecting 4He recoil nuclei and electrons in coincidence with the high resolution spectrometers of the Hall A Facility of Jefferson Lab. The measurements have uncovered a second diffraction minimum for the form factor, which was predicted in the Q2 range of this experiment. The data are in qualitative agreement with theoretical calculations based on realistic interactions and accurate methods to solve the few-body problem.
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Comparison of commercial influenza A virus assays in detecting avian influenza H7N9 among poultry cloacal swabs, China. J Clin Virol 2014; 59:242-5. [PMID: 24529843 DOI: 10.1016/j.jcv.2014.01.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Revised: 01/12/2014] [Accepted: 01/15/2014] [Indexed: 11/16/2022]
Abstract
BACKGROUND Avian H7N9 virus emerged in China in February 2013 and has since spread widely among China's poultry, causing numerous human infections. OBJECTIVES To compare World Health Organization (WHO) and US commercial influenza assays in detecting avian H7N9 virus in poultry cloacal specimens. STUDY DESIGN Between April 6 and July 15, 2013, 261 cloacal swabs were collected from commercial poultry in Nanjing and Wuxi City, Jiangsu Province, China. Swabs were screened with the WHO's influenza A and H7N9 real-time RT-PCR (qRT-PCR) assays. A blinded panel of 97 specimens (27 H7N9-positive and 70 influenza A-negative) was then used to compare 3 antigen based commercial assays (Remel Xpect Flu A&B, Quidel Quickvue influenza, and Quidel Sofia Influenza A+B), and 2 molecular commercial assays (Quidel Molecular Influenza A+B assay and Life Technologies VetMAX™-Gold SIV Detection Kit). None of these commercial assays were approved for use with poultry specimens. RESULTS Considering the WHO H7N9 qRT-PCR assay as the gold standard, all assays except the Quidel Quickvue influenza assay had high specificity (ranging from 96 to 99%). Regarding sensitivity, the Life Technologies VetMAX™-Gold SIV Detection Kit (100%; 95% CI 87-100%) and the Quidel Molecular Influenza A+B assay (85%; 95% CI 66-96%) performed the best. The sensitivities of the non-molecular antigen detection assays were either unable to detect small amounts of H7N9 viral RNA or were inhibited by specimen type. CONCLUSIONS The Life Technologies VetMAX™-Gold SIV Detection Kit and the Quidel Molecular Influenza A+B assay are comparable in performance to the WHO H7N9 qRT-PCR assay in detecting H7N9 from poultry cloacal specimens.
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Sparse evidence for equine or avian influenza virus infections among Mongolian adults with animal exposures. Influenza Other Respir Viruses 2013; 7:1246-50. [PMID: 23941547 PMCID: PMC4634246 DOI: 10.1111/irv.12148] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/12/2013] [Indexed: 12/21/2022] Open
Abstract
In recent years, Mongolia has experienced recurrent epizootics of equine influenza virus (EIV) among its 2·1 million horses and multiple incursions of highly pathogenic avian influenza (HPAI) virus via migrating birds. No human EIV or HPAI infections have been reported. In 2009, 439 adults in Mongolia were enrolled in a population‐based study of zoonotic influenza transmission. Enrollment sera were examined for serological evidence of infection with nine avian, three human, and one equine influenza virus strains. Seroreactivity was sparse among participants suggesting little human risk of zoonotic influenza infection.
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Recovery of live virus after storage at ambient temperature using ViveST™. J Clin Virol 2012; 56:57-61. [PMID: 23046621 DOI: 10.1016/j.jcv.2012.09.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Revised: 09/11/2012] [Accepted: 09/13/2012] [Indexed: 11/29/2022]
Abstract
BACKGROUND A major impediment to performing virological field studies in developing nations is the lack of ultra-low freezers as well as the expense and difficulty of shipping frozen samples. A commercially available product, ViveST™, was developed to preserve nucleic acids at ambient temperature for use in specimen storage and transportation. However, its applications as a viral storage, transport and recovery device have not been evaluated. OBJECTIVE To examine the ability of ViveST to preserve live virus following storage at ambient temperature. STUDY DESIGN A panel of six viruses was stored at ambient temperature (~22°C) in ViveST with fetal bovine serum (FBS), or ViveST with minimal essential media (MEM) and compared with virus stored in universal transport media (M4RT), MEM, and FBS alone. Stored viruses included: human adenovirus (14p), dengue virus 2 (16608), echovirus 3 (Morrisey), human rhinovirus 15 (1734), Coxsackie virus B5 (Faulkner), and herpes simplex virus 1 (HF). After 7 days storage at ambient temperature, virus recovery was measured via titration using viral plaque assays or focus-forming unit assays. RESULTS Viral titer studies indicate that ViveST with either FBS or M4RT preserved/recovered 5 different viruses for 1 week at ambient temperature. MEM preserved 4 viruses while FBS and ViveST with MEM preserved 3 viruses each. Statistical analyses indicate that M4RT and ViveST with FBS preserved significantly more virus than the other treatments. CONCLUSIONS These data suggest that ViveST with either FBS or M4RT may be useful in field specimen collection scenarios where ultra-cold storage is not available.
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Seeking the mission-minded. TRUSTEE : THE JOURNAL FOR HOSPITAL GOVERNING BOARDS 2012; 65:31-1. [PMID: 22787902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
A rural hospital attracts clinicians who want to care for the underserved at home and abroad.
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Directed flow of identified particles in Au+Au collisions at √[SNN]=200 GeV at RHIC. PHYSICAL REVIEW LETTERS 2012; 108:202301. [PMID: 23003142 DOI: 10.1103/physrevlett.108.202301] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2011] [Indexed: 06/01/2023]
Abstract
STAR's measurements of directed flow (v1) around midrapidity for π±, K±, KS0, p, and p[over ¯] in Au+Au collisions at √[sNN]=200 GeV are presented. A negative v1(y) slope is observed for most of produced particles (π±, K±, KS0, and p[over ¯]). In 5%-30% central collisions, a sizable difference is present between the v1(y) slope of protons and antiprotons, with the former being consistent with zero within errors. The v1 excitation function is presented. Comparisons to model calculations (RQMD, UrQMD, AMPT, QGSM with parton recombination, and a hydrodynamics model with a tilted source) are made. For those models which have calculations of v1 for both pions and protons, none of them can describe v1(y) for pions and protons simultaneously. The hydrodynamics model with a tilted source as currently implemented cannot explain the centrality dependence of the difference between the v1(y) slopes of protons and antiprotons.
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A comparison of viral fitness and virulence between emergent adenovirus 14p1 and prototype adenovirus 14p strains. J Clin Virol 2012; 54:265-8. [PMID: 22484030 DOI: 10.1016/j.jcv.2012.03.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Revised: 03/06/2012] [Accepted: 03/08/2012] [Indexed: 10/28/2022]
Abstract
BACKGROUND Epidemiological studies from the last decade have suggested that the morbidity and mortality associated with a newly emergent strain of human adenovirus (HAdV-14p1) is greater than other, more prevalent, adenovirus strains. Recent molecular analysis identified very minor genetic differences in HAdV-14p1 compared to prototype HAdV-14p. No studies have evaluated how these differences may affect virulence. OBJECTIVE To compare HAdV-14p1 and HAdV-14p strains for competitive fitness and virulence. STUDY DESIGN We performed in vitro and molecular assays to evaluate growth kinetics, cellular infectivity, cytotoxicity, and plaque morphology of the two strains. RESULTS Growth kinetic data showed no viral replication at 30°C and minimal differences at 37°C for both strains. Cellular infectivity data showed propagation capabilities for both strains in a diverse array of cell lines, with human lung and kidney cells having the highest propagation potential. Cytotoxicity data indicated cellular distress differences induced by both strains of virus in the first 12h, but similar distress levels between 12 and 48 h. Plaque morphology assays showed some differences in average plaque diameter. CONCLUSIONS These data suggest that the increase in morbidity and mortality observed in recent HAdV-14p1 infections is not due to viral growth or cellular infectivity differences from the prototypic HAdV-14 strain. While there were some statistically important differences detected between strains in cytotoxicity and plaque morphology assays, it seems more likely that other factors, such as environmental stressors, co-infections, or individual host response are likely contributing to the increase in morbidity.
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Identified hadron compositions in p+p and Au+Au collisions at high transverse momenta at √S(NN)=200 GeV. PHYSICAL REVIEW LETTERS 2012; 108:072302. [PMID: 22401197 DOI: 10.1103/physrevlett.108.072302] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2011] [Indexed: 05/31/2023]
Abstract
We report transverse momentum (p(T)≤15 GeV/c) spectra of π(±), K(±), p, p[over ¯], K(S)(0), and ρ(0) at midrapidity in p+p and Au+Au collisions at √S(NN)=200 GeV. Perturbative QCD calculations are consistent with π(±) spectra in p+p collisions but do not reproduce K and p(p[over ¯]) spectra. The observed decreasing antiparticle-to-particle ratios with increasing p(T) provide experimental evidence for varying quark and gluon jet contributions to high-p(T) hadron yields. The relative hadron abundances in Au+Au at p(T)≳8 GeV/c are measured to be similar to the p+p results, despite the expected Casimir effect for parton energy loss.
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Strangeness enhancement in Cu-Cu and Au-Au collisions at √S(NN)=200 GeV. PHYSICAL REVIEW LETTERS 2012; 108:072301. [PMID: 22401196 DOI: 10.1103/physrevlett.108.072301] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2011] [Indexed: 05/31/2023]
Abstract
We report new STAR measurements of midrapidity yields for the Λ, Λ[over ¯], K(S)(0), Ξ(-), Ξ[over ¯](+), Ω(-), Ω[over ¯](+) particles in Cu+Cu collisions at √S(NN)==200 GeV, and midrapidity yields for the Λ, Λ[over ¯], K(S)(0) particles in Au+Au at √S(NN)==200 GeV. We show that, at a given number of participating nucleons, the production of strange hadrons is higher in Cu+Cu collisions than in Au+Au collisions at the same center-of-mass energy. We find that aspects of the enhancement factors for all particles can be described by a parametrization based on the fraction of participants that undergo multiple collisions.
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